45°方向地震作用下RC空间梁柱节点破坏机制研究

Damage Mechanism Research on Reinforced Concrete Spatial Joints Subjected to 45-degree Direction Cyclic Loading

摘要: 汶川地震中大量钢筋混凝土结构房屋柱端严重破坏、甚至引起房屋倒塌,没有形成“强柱弱梁”破坏机制.本文从空间梁柱节点受力分析、模型试验和有限元数值分析3个方面论述了钢筋混凝土空间梁柱节点在45°方向地震作用下的破坏机制,在现行抗震设计规范规定沿结构两个主轴方向分别计算地震作用并进行抗震验算的设计方法中,没有考虑45°方向地震作用是造成不能形成“强柱弱梁”破坏机制的主要原因之一,指出了在框架结构“强柱弱梁”抗震设计中应考虑45°方向地震作用的必要性.

Abstract: The prefered strong-column weak-beam mechanism had not been realized in Wen-Chun earthquake and many buildings have been damaged for the reason of it.In this paper the damage mechanism of the spatial joint under the 45-degree direction earthquake affection was discussed through the mechanical analysis,cyclic loading experiment and the finite element analysis.The aseismic design method prefered in the code have not considered the 45-degree direction earthquake affection and it is considered as one of the main reason that the strong-column weak-beam mechanism had not been realized in earthquake,the necessity of the 45-degree direction aseismic designing is also suggested.